1. Field of the Invention
The present invention is in the field of resistance welding pins of the type used to hold a fibrous insulating batt to the surface of ducting used in air conditioning, heating, and like air conduit installations.
2. The Prior Art
The present invention is directed to an improved welding in fabricated of sheet metal, and more particularly to an improved version of the welding pin disclosed in U.S. Pat. No. 3,701,878.
In the noted patent there is shown a sheet metal resistance welding pin which may be stacked or nested in compact fashion, the pins being disposed in a shingled relationship in the stacked condition, e.g. the head and shank portions of adjacent pins are in abutting and slightly laterally offset relation. In U.S. Pat. No. 3,762,541 there is disclosed mechanism for supporting in stacked or nested position and serially feeding the welding pins of U.S. Pat. No. 3,701,878.
Certain types of known feeding and orienting apparatuses incorporate hoppers and selector mechanisms for serially removing randomly positioned individual articles one at a time and feeding the same in a predetermined desired orientation to an apparatus for further processing the same, e.g. to a welding head. It is important to the satisfactory operation of such feeding apparatuses that the articles to be extracted from the hopper be capable of ready separation. The welding pins in accordance with U.S. Pat. No. 3,701,878 are not ideally suited for use with hoppers of the type described in view of the tendency of such pins to stack and wedge together or stick in the stacked position. Stacked pins cannot be fed or, in some instances, may be fed several at a time, resulting in improper affixation.